DOI https://doi.org/10.36487/ACG_repo/2645_82
Cite As:
Vallati, O, Wang, J & Young, P 2026, 'Consumed capacity monitoring of Sandvik MD and MDX bolts using ultrasonic pulse echo', in A van As, D Cumming-Potvin & J Wesseloo (eds),
Caving 2026: Proceedings of the Sixth International Conference on Block and Sublevel Caving, Australian Centre for Geomechanics, Perth, pp. 1-11,
https://doi.org/10.36487/ACG_repo/2645_82
Abstract:
Rockbolt degradation poses a major challenge in caving operations as dynamic stresses and progressive deformation reduce reinforcement capacity. Recent studies, including MRIWA GSSO2, have identified the lack of low-cost, reliable instrumentation for measuring bolt elongation as a critical gap in effective ground support management.
To address this limitation, Sandvik introduces xCell Banshee, an innovative monitoring approach that integrates ultrasonic pulse echo technology into every MD and MDX bolt manufactured by Sandvik, enabling non-destructive, in situ measurement of bolt length, elongation, and consumed capacity. This universal implementation ensures that ground support monitoring becomes a standard feature across MD and MDX bolts, setting a new benchmark for safety and performance in underground mining. Importantly, the system is designed to be largely deployable and truly scalable on site, enabling mine-wide instrumentation without specialised installation procedures or additional hardware.
The paper first reviews current practices in caving operations for assessing rockbolt capacity and their limitations. It then introduces xCell Banshee, the new technology, explaining the underlying measurement principles, and details the laboratory testing program undertaken to validate the approach.
Laboratory investigations assessed measurement accuracy under varying loading conditions. Tests conducted on 2.4 and 3 m bolts demonstrate robust signal performance and strong agreement between ultrasonic measurements and mechanically measured elongation. Calibration trials identified a systematic length correction factor and quantified temperature effects, leading to the development of compensation algorithms suitable for field application.
The xCell Banshee system represents a significant advancement in ground support monitoring by providing real-time, non-destructive assessment of rockbolt integrity and deformation. Integration with digital monitoring platforms enables predictive maintenance strategies and has the potential to significantly enhance safety and performance in caving operations.
Keywords: MD, MDX, rockbolt, ground support, monitoring, capacity
References:
ASTM International 2020, Standard Practice for Measuring the Change in Length of Bolts Using the Ultrasonic PulseEcho Technique (ASTM E168520), West Conshohocken.
Darlington, B, Farrington, M & Vallati, O 2024, ‘The development of the peg bolt’, in P Andrieux & D Cumming-Potvin (eds), Deep Mining 2024: Proceedings of the 10th International Conference on Deep and High Stress Mining, Australian Centre for Geomechanics, Perth, pp. 517–528,
Lama, B & Momayez, M 2023, ‘Review of nondestructive methods for rock bolts condition evaluation’, Mining, vol. 3, no. 1,
Kaiser, PK & Moss, A 2022, ‘Deformationbased support design for highly stressed ground with a focus on rockburst damage mitigation’, Journal of Rock Mechanics and Geotechnical Engineering, vol. 14, no. 1, pp. 50–66,
Kamp, C 2022, ‘Management of production drift convergence and redevelopment’, in Y Potvin (ed.), Caving 2022: Proceedings of the Fifth International Conference on Block and Sublevel Caving, Australian Centre for Geomechanics, Perth,
Pan, Q, Pan, R, Shao, C, Chang, M & Xu, X 2020, ‘Research review of principles and methods for ultrasonic measurement of axial stress in bolts’, Chinese Journal of Mechanical Engineering, vol. 33, no. 1,
Potvin, Y, Wesseloo, J, Hadjigeorgiou, J, Mbenza, J, Cumming-Potvin, D, Sewnun, D … Morissette, P 2021, Ground Support Systems Optimisation Phase 2 (GSSO 2), MRIWA Report No. 497, Australian Centre for Geomechanics, Perth.
Potvin, Y & Hadjigeorgiou, J 2020, Ground Support for underground mines, Australian Centre for Geomechanics, Perth.
Song, G, Li, W, Wang, B & Ho, SCM 2017, ‘A review of rock bolt monitoring using smart sensors’, Sensors, vol. 17, no. 4,
Sun, Z, Wu, KT, Kruger, SE, Levesque, D, Gagnon, D, Quenneville, Y, … Royer, R 2019, ‘A new paradigm in ground support monitoring through ultrasonic monitoring of clusters of rockbolts', in J Hadjigeorgiou & M Hudyma (eds), Ground Support 2019: Proceedings of the Ninth International Symposium on Ground Support in Mining and Underground Construction, Australian Centre for Geomechanics, Perth, pp. 75–84,
Tadolini, SC 1990, Evaluation of Ultrasonic Measurement Systems for Bolt Load Determinations, Report of Investigations 9332, US Department of the Interior, Bureau of Mines, Washington.
Vallati, O, Roach, W & Weaver, S 2020, ‘Ground support and strata monitoring: what is needed?’, in J Wesseloo (ed.), UMT 2020: Proceedings of the Second International Conference on Underground Mining Technology, Australian Centre for Geomechanics, Perth, pp. 285–296,